Ernest chaeles lindemam



: v-.(.Nv0 M 2 Sheets-Sheet 1.

VB. 0. LINDEMANN.

UNDERGROUND OONDUIT FOR ELECTRIC WIRES.

N0. 376,893. Patented Jan. 24,1888.

- FIE I- FIG I- A. Q \X I @@ZM i N. FETER& Phnlo-Lilhographur, Washinglnn, D C.

(N Model.) I asheet -sneem.

E. 0. LINDEMANN.

UNDERGROUND GONDUIT FOR ELECTRIC WIRES,

No. 376,893. 'PatentedIJa111-24;18 88; I

N. PETERS. Photo-Lilhngmpher. Wflshinglon, DEC.

I film/w UNITE STATES. PATENT OFFI E,-

ERNEST CHARLES LINDEMANN, OF BALTIMORE, MARYLAND.

,UNDERGROUNDICONDUIT FOR ELECTRIC WIRES.

SEECIPICATION forming part of Letters Patent N 0. 376,893, dated January/24,1888. I

Application filed November 2, 1887. Serial No. 254.045. (No model.)

To allzvhom it may concern.-

Be itknown that I, ERNEST CHARLES LINDE- MANN, of the city of Baltimore and State of Maryland, have invented certain Improvements in Underground Conduits for'Electric and other Wires, of which the following is a specification.

In'the description of the said invention which follows, reference is made-to theaccompanying drawings, forming apart hereof, and in which i i v Figure I is a longitudinal side section of the conduit, and Fig. If an end view of the same. Fig. III is a side section of a part of the conduit, in which is situated a chamber provided with devices hereinafter described, to which certain of the wires may be secured and insu-- luted. Fig. IV is an end view ofthe said chamber. Fig. V is a"longitudinal side section ofa part ofa conduit containing branches for wires, and Fig. VI is a sectional plan of Similar letters of reference indicate similar parts in all the figures. In the said drawings, A A are conduitblocks, formed of concrete of non-conducting character, having holes atherein for electric or other wires. Theseblocks are adapted to be connected to each other; and with this View Fig. V.

one end ofeach block has a dovetailed projection, b, while the other end is recessed,

which recess ctis parallel in width and height and provided with a groove, d, which extends entirely around it, as shown. a

In connecting two blocks of the conduit together some plastic material is employed,

which fills up the spaces between the dovetailed projection and the inner face of the re- I cess c. The grooved being filled with cement, it becomes impossible after'the cement hardens to separate the sections without fracturing them.

Referring to Figs. III and IV, it will be seen that the chamber B is provided with insulating-glassesf, which are placed over wooden 45 pins or stems g, screwed into-the threaded holes in the removable top 0, the bottom I), and the sides E of the chamber BI As these chambers are quite limited in size, itis imholes. Consequently they cannot be perfectly secured except by having the holes threaded,

. as described.

,. In many cases it is necessary to uniteablock containing a number of wires to one having a 55. less number, which is douethrough the medium of test-boxes. Itherefore make the sections with the reduced number of holes of av less depth than the others, and fill thespace bepossible to drive the pins or stems g-intotheir' 5o tween the reduced projection and theinner 6o face of the recess with a liner-block,h, having grooves therein, as shown in Fig. III. By

this means I am enabled to economize in ma:

terial. I

Figs. V and VI show a 7 having branches, and it will be seen that these branches'terminate in a similar manner to the main blocks asregards' the, projections. and

projection-of a reduced size, and a grooved crossing or a block 6 5 liner-block adaptedto reduce the size of. the 75 recess, substantially as and for'the purpose specified.

ERNEST CHARLES LINDEMANN. 1

Witnesses:

WM. T. HOWARD, .DANL'. FISHER. 

